<%
  session.setAttribute("username","wyh");
%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>SessionCase</title>
</head>
<body>
  <h1><%=session.getAttribute("username")%></h1>
  <% session.invalidate(); %>
</body>
</html>
